From aafc801d691fb216d3975b0719ad1dd1b3eab527 Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Thu, 29 Jun 2023 00:46:41 +0000 Subject: [PATCH] Make the Elaboratable trait take clauses --- compiler/rustc_infer/src/traits/util.rs | 82 +++++++++++++------------ 1 file changed, 42 insertions(+), 40 deletions(-) diff --git a/compiler/rustc_infer/src/traits/util.rs b/compiler/rustc_infer/src/traits/util.rs index 847b267b6144d..66389cf59957c 100644 --- a/compiler/rustc_infer/src/traits/util.rs +++ b/compiler/rustc_infer/src/traits/util.rs @@ -80,14 +80,14 @@ pub struct Elaborator<'tcx, O> { pub trait Elaboratable<'tcx> { fn predicate(&self) -> ty::Predicate<'tcx>; - // Makes a new `Self` but with a different predicate. - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self; + // Makes a new `Self` but with a different clause that comes from elaboration. + fn child(&self, clause: ty::Clause<'tcx>) -> Self; - // Makes a new `Self` but with a different predicate and a different cause - // code (if `Self` has one). + // Makes a new `Self` but with a different clause and a different cause + // code (if `Self` has one, such as [`PredicateObligation`]). fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, span: Span, parent_trait_pred: ty::PolyTraitPredicate<'tcx>, index: usize, @@ -99,18 +99,18 @@ impl<'tcx> Elaboratable<'tcx> for PredicateObligation<'tcx> { self.predicate } - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self { + fn child(&self, clause: ty::Clause<'tcx>) -> Self { Obligation { cause: self.cause.clone(), param_env: self.param_env, recursion_depth: 0, - predicate, + predicate: clause.as_predicate(), } } fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, span: Span, parent_trait_pred: ty::PolyTraitPredicate<'tcx>, index: usize, @@ -123,7 +123,12 @@ impl<'tcx> Elaboratable<'tcx> for PredicateObligation<'tcx> { span, })) }); - Obligation { cause, param_env: self.param_env, recursion_depth: 0, predicate } + Obligation { + cause, + param_env: self.param_env, + recursion_depth: 0, + predicate: clause.as_predicate(), + } } } @@ -132,18 +137,18 @@ impl<'tcx> Elaboratable<'tcx> for ty::Predicate<'tcx> { *self } - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self { - predicate + fn child(&self, clause: ty::Clause<'tcx>) -> Self { + clause.as_predicate() } fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, _span: Span, _parent_trait_pred: ty::PolyTraitPredicate<'tcx>, _index: usize, ) -> Self { - predicate + clause.as_predicate() } } @@ -152,18 +157,18 @@ impl<'tcx> Elaboratable<'tcx> for (ty::Predicate<'tcx>, Span) { self.0 } - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self { - (predicate, self.1) + fn child(&self, clause: ty::Clause<'tcx>) -> Self { + (clause.as_predicate(), self.1) } fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, _span: Span, _parent_trait_pred: ty::PolyTraitPredicate<'tcx>, _index: usize, ) -> Self { - (predicate, self.1) + (clause.as_predicate(), self.1) } } @@ -172,18 +177,18 @@ impl<'tcx> Elaboratable<'tcx> for (ty::Clause<'tcx>, Span) { self.0.as_predicate() } - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self { - (predicate.expect_clause(), self.1) + fn child(&self, clause: ty::Clause<'tcx>) -> Self { + (clause, self.1) } fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, _span: Span, _parent_trait_pred: ty::PolyTraitPredicate<'tcx>, _index: usize, ) -> Self { - (predicate.expect_clause(), self.1) + (clause, self.1) } } @@ -192,18 +197,18 @@ impl<'tcx> Elaboratable<'tcx> for ty::Clause<'tcx> { self.as_predicate() } - fn child(&self, predicate: ty::Predicate<'tcx>) -> Self { - predicate.expect_clause() + fn child(&self, clause: ty::Clause<'tcx>) -> Self { + clause } fn child_with_derived_cause( &self, - predicate: ty::Predicate<'tcx>, + clause: ty::Clause<'tcx>, _span: Span, _parent_trait_pred: ty::PolyTraitPredicate<'tcx>, _index: usize, ) -> Self { - predicate.expect_clause() + clause } } @@ -252,14 +257,13 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { }; let obligations = - predicates.predicates.iter().enumerate().map(|(index, &(mut pred, span))| { + predicates.predicates.iter().enumerate().map(|(index, &(mut clause, span))| { // when parent predicate is non-const, elaborate it to non-const predicates. if data.constness == ty::BoundConstness::NotConst { - pred = pred.without_const(tcx); + clause = clause.without_const(tcx); } elaboratable.child_with_derived_cause( - pred.subst_supertrait(tcx, &bound_predicate.rebind(data.trait_ref)) - .as_predicate(), + clause.subst_supertrait(tcx, &bound_predicate.rebind(data.trait_ref)), span, bound_predicate.rebind(data), index, @@ -333,17 +337,15 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { if r.is_late_bound() { None } else { - Some(ty::PredicateKind::Clause(ty::ClauseKind::RegionOutlives( - ty::OutlivesPredicate(r, r_min), + Some(ty::ClauseKind::RegionOutlives(ty::OutlivesPredicate( + r, r_min, ))) } } Component::Param(p) => { let ty = tcx.mk_ty_param(p.index, p.name); - Some(ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives( - ty::OutlivesPredicate(ty, r_min), - ))) + Some(ty::ClauseKind::TypeOutlives(ty::OutlivesPredicate(ty, r_min))) } Component::UnresolvedInferenceVariable(_) => None, @@ -351,8 +353,9 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { Component::Alias(alias_ty) => { // We might end up here if we have `Foo<::Assoc>: 'a`. // With this, we can deduce that `::Assoc: 'a`. - Some(ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives( - ty::OutlivesPredicate(alias_ty.to_ty(tcx), r_min), + Some(ty::ClauseKind::TypeOutlives(ty::OutlivesPredicate( + alias_ty.to_ty(tcx), + r_min, ))) } @@ -362,10 +365,9 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { None } }) - .map(|predicate_kind| { - bound_predicate.rebind(predicate_kind).to_predicate(tcx) - }) - .map(|predicate| elaboratable.child(predicate)), + .map(|clause| { + elaboratable.child(bound_predicate.rebind(clause).to_predicate(tcx)) + }), ); } ty::PredicateKind::Clause(ty::ClauseKind::TypeWellFormedFromEnv(..)) => {